There are commercially available a large number of flashlights of many different configurations to suit different purposes. Flashlights are produced which use a wide range of battery sizes, as for example, AAA, AA, C, D, etc. Also, the materials of which flashlights are constructed vary widely. Some have metal bodies and glass or plastic lenses and plastic or metal reflectors, others have plastic bodies. The method of operating flashlights, that is, turning them on and off also varies greatly. Some flashlights for example, are operated by pressing, flipping, sliding or twisting an on-off switch mounted in the body of the flashlight and others are operated by rotating the head of the flashlight (where the light emerges) relative to the body. This rotation turns the flashlight on or off, and with some designs also varies the focus. In some flashlights, the batteries are inserted or removed by removing the head of the flashlight, in others by removing the base of the flashlight and with still others either or both may be removed and the batteries inserted or removed from either end.
The MAGLITE.TM. line of flashlights manufactured by Mag Instruments, Inc. of Ontario, Calif. are examples of metal bodied flashlights. They exist in a number of different configurations for different battery sizes and different numbers of batteries, e.g., 1 to 2 AAA or AA cells, 2 to 5 C cells, 2 to 6 D cells, etc. The versions manufactured by Mag Instruments, Inc. adapted to use AAA and AA size batteries are referred to as MINI MAGLITE.TM. flashlights. The MINI MAGLITE.TM. flashlights are turned on and off by rotating the head of the flashlight. Somewhat similar flashlights are also supplied by the Brinkman Corp. of Dallas, Tex. and by Streamlight, Inc. of Norristown, Pa. Flashlights of this type from these several different manufacturers often have in common that, (a) they use of one or two small batteries, e.g., AAA or AA cell batteries, (b) they are of substantially all metal construction (e.g. metal bodies, heads and bases), and (c) the on/off switching is accomplished by rotating the head of the flashlight relative to the body. Generally the base of the flashlight is removed for insertion and removal of the batteries and the head is removed for bulb replacement, but some work both ways. Small bi-pin, base-less, bulbs are also generally a common feature of these small AAA or AA cell, metal cased flashlights. Such flashlights are extremely popular because of their convenient size, ruggedness, durability and reasonable brightness. They are sold in very large quantities, probably exceeding a million a year. As used herein, the words "small metal case flashlight", singular or plural, are intended to refer generally to the MINI MAGLITE.TM. type of flashlight and its substantial equivalents, i.e., those having most or all of features (a)-(c) listed above. G. T. Price Products, Inc. of Los Angeles, Calif. is another maker of similar flashlights, but with a separate switch.
While many of these small metal case flashlights are used for general purposes, they are also particularly well suited for use in connection with firearms. For example, a number of mounts exist which allow versions of the small metal case flashlights to be mounted under or alongside a gun barrel so that when activated, they illuminate targets in the weapon boresight. The 1-2 AAA or AA cell versions are especially convenient in this application. While flashlights adapted to use larger battery sizes (e.g., C or D cells) are available, they are less convenient because of their greater weight and physical size because of the larger battery sizes. Thus, the AAA and AA cell small metal case flashlights are generally preferred, with the 2-cell versions being the most common.
When used in connection with weapons, illumination brightness and focus are especially important. While many of the available 1 to 2 AAA or AA cell small metal case flashlights provide adequate light beam focus, they do not provide sufficient light beam brightness. Thus, there is an ongoing need to obtain brighter light beams from such flashlights. Because of the very large number of such small metal case flashlights that already exist, it is desirable that the means for providing greater brightness be retrofitable to such existing small metal case flashlights so that there is no need to change the dimensions or arrangement of the weapon mounts that already exist and accommodate such existing small metal case flashlights, and so that persons who have already purchased such small metal case flashlights (and/or mounts therefore) may readily upgrade their flashlights to improve brightness without having to discard what they already have.